Eyed Brown (Satyrodes eurydice) (Linnaeus, 1763)

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Diagnosis: The Eyed Brown is yellowish brown, and has a generally faded look, even when fresh. Above and below, it has four pale-bordered dark spots on the forewing and six on the hindwing. Above, the spots are slightly blurred and the lower ones on each wing sometimes have small white pupils. On the underside, the spots are much more distinct and always have white pupils (the lowest spot has two), and are surrounded by concentric rings of light and dark. A dark line on the underside separating the light outer third of both wings from the darker basal portion is distinctly zigzagged. Wingspan: 38 to 48 mm.

Subspecies: There are two subspecies, but only the nominate subspecies is found in Canada.

Range: The Eyed Brown flies throughout the northeastern and north-central U.S., and in Canada from Cape Breton, Nova Scotia, across southern Canada as far as eastern Alberta and extending as far north as Baie-Kapotagen, Quebec, Malachi, Ontario, and The Pas, Manitoba. There is an old record from Great Slave Lake, Northwest Territories.

Similar Species: The Appalachian Brown (Satyrodes appalachia) is purplish brown, not yellowish brown, and the dark line on the underside is gently curved, not zigzagged. [compare images]

Early Stages: The larvae are green, with a dark green dorsal stripe and alternating dark and light green lateral stripes, with green tails. The head is green with red horns and has a red line from the horn to the eyes. They feed on sedges, usually Carex lacustris, Carex atherodes, and Carex rostrata, and hibernate as half-grown larvae. They are often reported to feed on Carex stricta, but in eastern Ontario and western Quebec single-species stands of this sedge never have colonies of eurydice, which seems to prefer only broad-leafed sedges.

Flight Season: It flies from mid-June to early September, but is most abundant in July. There is one generation per year.

Habits: The Eyed Brown is habitat-restricted to areas of sedges, often in small roadside sedge patches. Even where large populations occur in extensive wet areas, the butterflies seldom stray any distance. They have a slow, weak flight, often alighting on the sedges.